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Mike writes "As lighting manufacturers phase out the incandescent bulb, and CFLs look set to define the future of lighting, Panasonic recently unveiled a remarkable 60-watt household LED bulb that they claim can last up to 19 years (if used 5-1/2 hours a day). With a lifespan 40 times longer than their incandescent counterparts, Panasonic's new EverLed bulbs are the most efficient LEDs ever to be produced. They are set to debut in Japan on October 21st. Let's hope that as the technology is refined their significant cost barrier will drop — $40 still seems pretty pricey for a light bulb, even one that promises to save $23 a year in energy costs."

Why the hell is this offtopic? It's true - this hippie-frenzy focus on non-incandescent light sources is idiotic. Any time you're running any kind of active heating, the thermal inefficiency of incandescent lights becomes a nonissue because the heat output is not wasted. And with the usage cycle they're talking about, a $0.90 incandescent bulb should last at least 2 years. While I agree that it's nice to see LED lighting starting to measure up to the good old bulb-and-tungsten-wire approach, I don't think t

So incandescent bulbs are a bad thing in most of the world for about a third of the year (summer) and in some of the world most of the year. If you happen to be running air-conditioning at the same time as an incandescent bulb, you're just pumping money out of the window.

Not to mention the fact that having a heat source 6 inches from your ceiling is generally not the most efficient way to heat a room. It makes far more sense to save the energy wasted from the bulb, and spend it in an efficient central heating system instead, where strategically placed radiators and vents can put the heat where it's actually needed.

Even if we assume (incorrectly) that there is the same light usage in winter and summer, the marginal increase from paying double during the 2 months (maybe 3 during a bad summer) of AC are more than canceled out by 6 months where the bulb is redundant with the heater

If you replace your incandescents by CFL's or LED's you'll produce less heat from your lighting, so in winter you'll need to run the heater more. However the total electricity use will be the same.

In summer (summer being defined as the months, weeks or days the heating is not being run) the heat from the incandescent will be wasted, and if you have air conditioning will make your air conditioning run harder.

The case for CFLs just isn't that compelling in a house where more than 50% of my annual electrical bill is electric heaters.

Things will get better if you dump your electric heaters. They are expensive and there are shitloads of better systems available.

You save nothing on your heating bill. You just don't LOSE money from the heat provided. There's a big goddamn difference in those two concepts. Generally speaking, you'd spend the same amount of electricity if you are heating your home regardless if you used LED or Incandescent. If the temperature is comfortable outside and inside, you are wasting money heating your home by a small amount. If you are using AC, you are wasting money at TWICE the rate.

This assumes that you are using a resistance heater. If you use a heat pump (usually a COP of around 3-4) then you are still using extra power. (Every extra watt that you use with an incandescent could have done the same as between 1/3 to 1/4 of a watt with a heat pump).

The marginal increase in cost from the cooling is canceled out by the heating gains. That is, for every extra dollar I spend cooling heat that I produced with the light bulbs, I save at least an extra dollar off my heating bill.

Wah? You're losing me here.

Using silly made up numbers, assuming conservation of energy and double entry book-keeping:

Your heating bill is now $190 ('cos the CFL/LED is not giving you the heat it used to)Your lighting bill is now $10.

So your electricity bill is $200, $190 for heat and $10 for light.

In summer, with incandescents, your lighting bill is $100 and your air conditioning bill is $190.

In summer with CFL/LED's your lighting bill is $10 and your air conditioning bill is $100.

Like I said, silly made up numbers, and you can possibly correctly claim:

Correct. Unfortunately, CFLs and LEDs are much more expensive upfront. Since I get approximately zero savings for 6 months of the year, the time to recoup is doubled (or, with a fixed horizon, the price differential at the critical point is halved).

But that has nothing to do with your initial claim that the heating effect of incandescent bulbs in winter canceled out their electricity savings all year round.

Again, large upfront costs and smaller continued costs. It would cost a small fortune to replace our 1950s oil boiler with something vaguely modern.

Wah? You said you had electric heat! Is electricity cheaper than fuel oil in New England?

Oh, and I rent, so tearing stuff out is not an option.

But it's so easy to get a low rate loan to buy, and property is such a great investment!

Except that if you're using a heat pump vs resistance heating, the unit's SEER value comes into play. My units are SEER 13, so every unit of energy it takes to run the beast pumps 13 units of heat around.

So using incandescent lights for heat actually wastes money - that Watt going into the bulb could be used to provide 13 Watts of heat instead of just 1 (0.9, actually).

Heat pumps don't work in colder environments which, coincidentally, are also, usually, the places with the longest winters and shortest summers. In the warmer environments where a heat pump would be usable, the long summers would make much of the argument moot as the extra heat from the incandescent would be unwanted most of the year.

Yup. A halogen desk lamp makes a great accessory during Winter. It is more efficient than using a CFL and oil heating. I don't typically need to warm up my whole office, just the place I sit. The light also looks better than CFLs, or even regular incandescent bulbs. And halogen lamps are both hotter and 40% more efficient than regular incandescent bulbs.

Where I live the norm is to have thermostatically controlled gas central heating. Also the difference between summer and winter daylight hours is significant. Air conditioning is extremely rare in domestic properties anywhere in the U.K.

This means in the summer I hardly use artificial lighting, until late at night where the heat output of an incandescent light bulb can make a noticeable difference in taking the late night chill off a room.

I live in a high energy efficiency property in the UK as well, we moved to energy efficient bulbs around 18 months ago and have noticed a sufficient decrease in energy use to believe it was worthwhile.

Obviously I don't know nearly enough about your situation to advise you, but I am not persuaded that heat produced due to inefficiency of lightbulbs or other devices is an economical source of heating.

Your gas central heating is a much cheaper way to heat your house compared to incandescent bulbs.

Electricity is about 10-14p/kWh, and gas about 3p/kWh. Even with old heating it's still cheaper; my new condensing boiler is 85% efficient and was probably quite cheap (I rent, and everything else in the flat looks cheap), yours may well be even better.

I agree extra insulation is much more useful though. I'd like to see the government take the Green Party's economy-stimulation suggestion up: subsidise adding insulation to houses. Some incentive for landlords to add insulation would be good too, but I think this might happen with the home rating thing.

Me too. I've been using CFL's for almost twenty years, and I've come to the conclusion that they are a worse idea that using Edison's incandescent lighting. Here's why:

- CFLs have a power factor of around 0.5, which means they use twice as much power as rated. For example a 15 watt CFL uses 15 watts in your home, but then it uses another 15 watts at the central power plant due to the need to "rebalance" the power and restore the PF to 1.0. TOTAL == 30 volt-amps burned

After we bought our house I planned on replacing the vanity lights in the bathroom with CFLs as the current ones burned out. Part of it was that my wife complained about the bathroom getting too hot; I figured the less heat given off by the CFLs would help out there, too, plus if they lasted longer everybody would win. Well, I replaced two of them and they lasted maybe 6 months max - I'm sure the humidity from the shower wrecked them. Here's an application where they could save energy, and their cool-run

- CFLs have a power factor of around 0.5, which means they use twice as much power as rated. For example a 15 watt CFL uses 15 watts in your home, but then it uses another 15 watts at the central power plant due to the need to "rebalance" the power and restore the PF to 1.0. TOTAL == 30 volt-amps burned

Except that the power company puts PF correction in far sooner than the power plant, and while it doubles the amps for wire resistance calculations(until it hits the power company's correction equipment), it actually doesn't double the wattage used. More like 5-10%. They build PFC in pretty much as standard on high quality high efficiency computer power supplies, why would you think the power company couldn't do the same? And there are better bulbs out there with active PFC.

- New technologies have allowed folks like GE to build 60 watt incandescants that only use 30 watts while still providing the same brightness. So the net usage is the same as the CFL. No need to abandon the old bulbs.

Neat tech, but like I said, a 15 watt bulb with a PF of.5 doesn't mean it's using 30 watts. So the CFL still has a leg up of aobut 50% more light per watt than the new higher efficiency bulbs.

I have CFLS in my unheated north dakota garage. the 12 watters start a little slower in the winter, but are still going strong. I have a 23 watt(100watt equiv) in my bathroom. It's been there for over a year, hasn't quit yet. Not instant full brightness - but I like that for those midnight trips. I don't have a dimmer in my house, but it's a five minute job to swap the dimmer out with a CFL compatible one(remember to get a dimmable CFL).

It sounds like you're buying cheap bulbs, and your dimmer is probably the old resistance type, not the newer electronic pulse type.

- CFLs hate being turned on and off. Rapid cycling makes them die as quick as an incandescent bulb. So you've spent 5 times as much for a bulb than doesn't last any longer.

In 6 years the only CFL to die on me was from being dropped.

- CFLs have a warm-up time. Turn it on to read your paper, and you have to wait 5 minutes before you can see the writing. Turn it on to go down the basement stairs - and you can't see the steps because it's still too dim (a safety hazard).

For me it takes longer for my eyes to adjust to the new light level, open the book/paper, whatever. The 100 watt equivalent in the bathroom has the longest start-up time, and even it is pretty much instant on, just at ~40-60 watt equivalnet for the first 10 seconds.

If the stairs are too dim, put in a brighter bulb. Heck, I wonder where people like you are getting your slow starting CFLs from, because none of mine take that long. I have two incandescent bulbs left in closets, and the only reason they aren't CFLs yet is because they haven't died, and I use them too little to bother.

- CFLs have a warm-up time. Turn it on to read your paper, and you have to wait 5 minutes before you can see the writing. Turn it on to go down the basement stairs - and you can't see the steps because it's still too dim (a safety hazard).

For me it takes longer for my eyes to adjust to the new light level, open the book/paper, whatever. The 100 watt equivalent in the bathroom has the longest start-up time, and even it is pretty much instant on, just at ~40-60 watt equivalnet for the first 10 seconds.

>It sounds like you're buying cheap bulbs, and your dimmer is probably the old resistance type, not the newer electronic pulse type.

Not to dismiss your other arguments, but I work in lighting, specifically in designing test hardware for LED lights that run off commercially available dimmer switches, and I've spent years renovating houses, and I have never seen a resistance-type dimmer switch. The way a resistance dimmer would work, would be to dissipate the power through resistance in the wall, meaning

t doesn't matter. The point is that a 15 watt CFL is actually using 30 volt-amps, so it's only saving half as much energy as a 60 volt-amp traditional bulb

I'm a triple-degreed electrical engineer. Not an idiot.

You're a triple-degreed EE who doesn't know how power factor [wikipedia.org] works, and yes that does make you an idiot. Idiots can get degrees, who would have thought?! If you didn't have the degrees, then you'd just be excusably ignorant (but in either case a jackass for talking like you weren't ignorant).

CFLs have a warm-up time. Turn it on to read your paper, and you have to wait 5 minutes before you can see the writing

1990 called.. it wants its CFLs back. Have you *really* actually used them or are you just making stuff up?

I hear that on Slashdot a lot, and it's bunk. I've had the whole house on CFLs for years now and they light *instantly*. The only time I ever had one that needed to 'warm up' was one of the original Philips ones years ago.

CFLs in my house have died within a year: the ones installed in the bathroom and kitchen. They don't like the humidity and heat which is why I'm not surprised. The others have lasted since Feb 2007. Brands don't seem to matter.

It's unwritten law that you don't take the lightbulbs when you move house; It's just being a cheapskate. Like taking the carpets, or the hooks off the back of doors. My parents have had to walk around with candles before now because the idiot who sold the house too every bulb, and this was before the time of 24 hour shopping in the UK. They had to drag boxes out in front of the car to see what was in them.

I swear to God if anybody does that to me when I'm moving into the house they've sold, I'm turning up

In the US (well, the parts I've paid attention to) "real property" is the land and anything attached to it. If you can lift it and carry it out (with or without help) with nothing more than disconnecting it from utilities (or something like a dryer vent) then it not part of the real property. So you take the counter-top microwave with you, but not the one above the stove. You can take your fridge and washer/dryer, but not the dish washer. Stoves that slide out can be taken as well. In practice, the stove is left in place. The refrigerators are usually left as well, but not washer/dryers. It is a violation of the terms of sale for all standard sale agreements to take bulbs. If they were replaced with incandescents, no one would probably notice, but it would still be "illegal" to take them. If the sockets were left empty, I would expect that the buyer would press the issue. It's rude and a violation of contract to remove anything "secured" to the grounds, and you have to unscrew them to take them, so they are part of the real property. Blinds and curtain hardware are attached with screws or the like, and thus are also left, by law, in most of the US. The curtain fabric itself can be removed. Light fixtures must remain. Though, in the US, unlike the rest of the world, you can sign away what's guaranteed you by law, so you can make the buyer agree that you'll be taking them in direct contradiction to the law.

(What I would do if swapping to LED bulbs would be to put the bulbs I take out in a box somewhere and reinstate them when leaving.)

Yeah I would put cheap globes in too. On a different but related note I have a relative who, when he inspected a house he was buying would hide items which he wanted to own, then retrieve them after taking the place over.

Same here. They can last that long in theory, but the ballasts go dead in a year or two. If a LED works like it should, it will be ballast-free and actually last until the thing burns itself to a crisp inside.(ie - failure from wearing out vs defect)

Also, don't underestimate the benefit to the utility companies which have to generate extra power for CF bulbs vs other technologies. Less load means less brownouts and so on. If these are full-wave, in f

The problem with CCFL's is that short duty-cycle usage shortens their lifetimes. This makes them great for things like porch lighting, living rooms etc where they'll be on for hours at a time, but poor for things like bathrooms where they may be on for 10 minutes at a time tops. When used in situations that extend their lifetimes, CCFLs are indeed much more cost-effective than LEDs are currently, but as is usually the case, a mixed application of both will always be the winner. Also, I've noticed (in a very

I bought my first CFLs back in 2001 (six of them). All but one is still working. One, I had in a portable work light, and I busted it transporting it. The others survived a move to my new house in 2005.

As soon as the builders cheap incandescent lights began burning out (in 2006), I bought replacements for ALL non-dimmer lights in my house (mostly in bathrooms), about 25 bulbs. While not all of them are in use every day, every one of them is still working.

In a lamp test by a Finnish magazine the 3 EUR fluorescent lamp died at 3000 hours. The more expensive ones are still going on but starting to show longer warming times, stains/cracks and other problems. In addition to these problems fluorescents are hazardous waste and should be recycled. At 10x longer lifespan the LED light sounds like a good deal to me.

The bulb in TFA (I know, I know... but it wasn't in TFS) is rated 6.9w consumption, and is presumably the 60w-equivalent referenced in the summary. Most "60w" CFLs take around 12-15w if memory serves - so these LED bulbs are about twice as efficient. Save $23/yr for 19 years vs $12/yr for 5 years (you say 10, but they're usually rated to five and I've almost never seen one last more than two; they seem very sensitive to older wiring). It pays for itself in less than two years compared to an incandescent, and in four compared to a CFL.

Of course, that's all assuming they actually last that long. I don't doubt the power consumption ratings, but as I said I've never seen a CFL last anywhere near it's rated life. My understanding is that they have a limited number of starts due to the ignition ballast (which is external to the bulb in standard fluorescent tubes); I'd assume that if you have older wiring or other factors that may cause frequent power sags you'll burn through those starts unusually fast. That seems to be the case at my house, or would at least make some degree of sense to me. I could be dead wrong about the reasoning, but CFLs unquestionably die faster than incandescent bulbs around here. Hopefully this isn't an issue with LED bulbs.

In theory LEDs don't care about how many times they are switched. Normal LEDs are dimmed by adjusting the PWM - they are switched thousands of times per second - this is more efficient than simply using a bigger series resistor.

I say "in theory" because these LEDs could be different to "normal" LEDs. (Driver circuitry etc)

Look at the LEDs on your keyboard. If you are like most people with a desktop machine, the num lock is on all the time, and you never use the scroll lock. Even after a year, the scroll lock light will be about twice as bright as the num lock light.

Whoa, there, if you go from 60W to 6,9W you save 53W, if you go from 60W to 15W you save 45W, if saving 53W saves you 23$/y, saving 45W will save you 19,5$/y. But it still pays for itself in 10 years, a bit less if you take into account the price of the CFL.

$3000 se ms a lit le high to me too. I pai ted a gar ge once and fou d some merc ry rol ing arou d on the floor as I was pres ure wash ng. I just sco ped it up with a du tpan and put it in a jar. I'm perf ctly fine, it's not like I'm dead or hand ca ped or anyth ng now.

"Mercury concentration in the study room air often exceeds the Maine Ambient Air Guideline (MAAG) of 300 nanograms per cubic meter (ng/m3) for some period of time, with short excursions over 25,000 ng/m3, sometimes over 50,000 ng/m3, and possibly over 100,000 ng/m3 from the breakage of a single compact fluorescent lamp. "

The question is not whether the amount exceeds the standards set by the government (they are almost guaranteed to), but whether the amount actually absorbed into the body through the lungs is even near the amount absorbed by eating a piece of tuna. I don't have supporting evidence, but I would be willing to bet the tuna would lead to much more absorption. My main reason for guessing this is that the mercury in tuna is in organic compounds which are more likely to be absorbed than elementary mercury. It also

You forgot to finish your thought with "if you compeletely and unjustifiably overreact.

That's pretty much what businesses and schools do in our litigious age. A local school in my area was recently closed for two days over an old barometer that got dropped in one of the science classrooms. They brought in a professional cleanup crew and spent $80,000 to have the mercury spill cleaned up.

Now I can understand closing off the classroom where the spill happened but closing the whole school seems rather excessive to me. $80,000 for cleanup seems really excessive. But that's what they have to do in this day and age. Otherwise some parent would freak out ("OMG, you mean my kid was within a quarter mile of spilled mercury?! I read someone that stuff is as dangerous as Dihydrogen Monoxide!") and they'd be writing that $80,000 check to a law firm instead of a cleanup crew.

The mercury release caused by burning coal (burning coal releases quite a bit of mercury into the air) to produce the extra energy to run an incandescent for a year is more than the mercury contained in one CF.

Should CFs be disposed of properly? Yes.Is one broken CF a hazmat issue? No.

You only save $23 a year if you compare against an incandescent bulb, which is like comparing your car's fuel economy against a school bus. When you compare these bulbs to CFLs, they make much less economic sense, unless you're worried about Mercury pollution.

Well, most people still use incandescents. There are also some places where CFLs don't work as well, but an LED would be just fine.

Also, if you look a little further up, the LED lights still pay for themselves times two or so against CFLs over their lifetime. And that's with a brand new product. CFLs weren't a lot cheaper when they debuted.

Provided the claim has any base in reality. I have been using CFLs for years, and so far my luck with them has been uniformly bad. They burn out in 3 to 6 months in my application. Possibly my environment is too hot for the electronics inside.

A 60 watt bulb burning for 5.5 hours a day uses about 120KWH a year. My non-peak electricity (i.e. night time when I would be using the lights) is $0.063/kwh. That math is $7.60/YEAR for electricity. Electric rates would have to be almost $0.18US, which is my peak rate during the summer months (it drops to about $0.086US for what passes for winter in Phoenix.) So a 6watt LED bulb would use 1/10th of electricity, saving around $7/year.And I doubt if more than 3 of the incandescent bulbs are used more than

There are places where the cost to reach a light bulb to change it is prohibitive. It could be theater marquee lights, lights atop a vaulted ceiling, or places behind a recessed opening that takes a lot of disassembly to get to. So even though $40 might be expensive up front, not having to set up scaffolding 30-40 feet up to get to some fixtures is worth it to some.

Aren't LED lifetimes usually rated to the point at which they hit half brightness, not die completely? And don't white LEDs tend to turn blue over time due to the powder stuff (sorry, it's almost 4am, I can't be bothered to look up the technical term) they use to adjust the color to white fading unevenly, or something to that general effect?

In either case, it doesn't matter. If the apocalypse hasn't come in 19 years, you can bet your ass that we'll have much cheaper and better alternatives available.

A typical bulb sees 50Hz 110V or 240V coming into it. When the signal goes above 0V it starts to glow, when it goes below 0V it starts to glow, back and forth faster than the eye can see.LEDs don't work on a negative signal so the signal needs to be rectified. Half wave rectification means that when it goes above 0V you start getting power to the LED, when you go below 0V you don't. So the LED is on for only half the time. Full wave rectification flips the negative part to the positive side and you get some

And the capacitor is there to keep the current going for the time the voltage is around 0V. This isn't really a problem for incandescent light bulbs since they after-glow for the time there is no voltage on the bulb, so you get a consistent glow. This is not the case with CFL's as they only marginally afterglow, and even worse with LEDs since they don't glow at all when the power is cut.

Nobody would ever seriously run a production LED system like this. Typical forward voltage of white LEDs is around 3V. Supplying rectified AC would waste 97% of the energy on US 110V, thus making it less efficient that a halogen bulb and producing lots of heat in the resistor.

The things contain a switch mode power supply, like just about every small mains powered device nowadays. The SMPS converts input to a current output for LEDs, which is what they need for best efficiency. It does this on both halves of the AC cycle. This added complexity contributes to the cost, but not as much as you might think.

Early LED bulbs that ran off cheap transformers used for SELV lighting used series resistors, but the current is very variable and they are, basically, crap. They got away with it because big arrays of cheap LEDs were used. A long term solution really needs not more than two or three high power LEDs in an envelope, because this helps to drive down cost. But this requires an advanced power supply.

For what it's worth, my job is designing test hardware for LED drivers. As such I spend a lot of time taking apart other people's LED bulbs and seeing what they're doing. A scary number of current LED bulbs consist of a single diode, a big capacitor, and a string of LED's in series with their series forward voltage drop being roughly equal to 150 volts, and then a single current-limiting resistor at the end of the strand. That is the *worst* way I can think of to do the job. (Not to mention the cap they're using to smooth out the ripple is a very cheap electrolytic, with a lifetime of probably about 2000 hours if you're lucky, so that will be what fails.) The nicer low-end bulbs use a full wave bridge rectifier and sometimes even a linear regulator.

Of course, any good bulb worth buying uses an actual LED driver that acts as a constant current source. But even they still often use cheap electrolytics, meaning your LEDs will still have 95,000 hours of life in them when the bulb dies because the crappy caps they're using on the input and output sides of the switcher have failed.

If you're looking at a light and want to know generally what they're doing, see if you can count roughly how many LED's are in the fixture. If there are over 30, chances are it's a series string being run on rectified AC. If there are only a dozen or less, it's got a real driver and should at least give you reasonable efficiency, although no guarantees on lifetime. In an ideal world everyone would design LED drivers and use all ceramic or Nichicon caps, which have lifetimes measured in decades rather than months, but that'd cost a few pennies more and people will always buy the cheapest thing they can buy, particularly when you're working in a price range that's already an order of magnitude more expensive than the (incandescent) competition.

We still call them bulbs at work, but honestly I don't have a good way to distinguish between them. You'd have to pull it so far apart that it'd be useless. (The last bulb I repaired, I chucked up in my lathe and used a jeweler's saw to slice the translucent diffuser off, then pried the board with all the LED's mounted out of the body, then desoldered the leads that drove the LED's, before I could get to the failed electrolytic that caused the bulb to die.) I'm also reluctant to recommend specific manufa

A lot of LED christmas lights seem to have a visible flicker noticable from half a mile away. They probably don't have anything along the lines of smoothing capacitors in them. Hopefully we are talking about better technology though

The LED lights I've seen are too directed. They don't light up a room all that well. Whatever spot the LEDs are aimed at is more illuminated, and everywhere else less illuminated than with CFLs or incandescents.

The LED lights I've seen are too directed. They don't light up a room all that well. Whatever spot the LEDs are aimed at is more illuminated, and everywhere else less illuminated than with CFLs or incandescents.

This can usually be alleviated by a good design of emitter geometry, lens and diffuser. Unfortunately, designing good lenses is difficult, and fabricating and assembling the resulting complex shapes is expensive.

Panasonic recently unveiled a remarkable 60-watt household LED bulb that they claim can last up to 19 years

TFA

The bulbs use only an eighth the power of incandescents. That means a 60-watt-equivalent LED bulb would cost only 300 yen (about $3) a year instead of 2,380 yen ($25.80)--a significant savings over a lifetime.

The box pictured on the right has "6.9w", which if as good as a 60 watt incandescent, is probably only a watt or two better than the equivalent CFL.

This is because the really bright white LEDs are actually monochrome blue, they have a phosphor that converts some of that blue light into other colours, but not normally enough for a nice (sun like) colour.

There are other techniques that seem to convert the frequencies better; or they could use the old trick of putting different colour LEDs in one bulb. But for the moment if you want highest efficiency you're stuck with lots of blue in the light and a "cold" feel.

One point though, white LEDs are normally closer to the spectrum of the sun than incandescents, it's just that the blue spike is in the opposite direction to the very reduced blues you get from a incandescent. This is a known problem, so the conversions will continue to get better.

$40 still seems pretty pricey for a light bulb, even one that promises to save $23 a year in energy costs

You must be an accountant living on the outdated system of monthly and quarterly figures.
To have an amortisation within 2 years and outright profit for 17 years afterwards sounds like a pretty damn good investment.

While I wouldn't mind using LED as replacements when the existing CFL wear out, particularly if they are less toxic when discarded, what I really need is a replacement for halogen small US base and bayonet, along with a few "candelabra" small base bulbs. Dimming would be a plus.

I was talking to the facilities manager at the local University... about cost to replace bulbs in some of his buildings.. In some cases it is literally in the many tens of thousands of dollars range. They have to bring scaffolding in with a small crew to erect and move around. (Doors too small for a lift.)

He would be more than happy to pay $42/bulb IFF it meant he didn't have to go back in for two decades.

I just built a new house which has something like 32 GU10 spotlights built into the ceilings to provide lighting. An LED bulb uses ~1/25th the power of a traditional halogen so I could be turn on every single light in the house for little more than the cost of a single halogen. The initial outlay will pay for itself in a year or two. And I don't have to be climbing up ladders or risking my neck changing they so often because they last much longer.

The main issues to look for with LEDs is some of the cheaper ones give out a horrible ghostly white light. The box should say what colour temperature they output, and the best ones output 3200K warm white light similar to traditional incandescents. You wouldn't even know its an LED unless you stared at it. The other issue is only some bulbs work with dimmer switches, but there are models which do that too.

The case for LEDs in other kinds of fixtures is probably less clear cut. LEDs are fairly directional so they probably require some refractive covering to be useful in hang down bulbs. But in the meantime there are plenty of CFL solutions which again save a lot more than traditional incandescents. I really don't see why anyone would bother with incandescent bulbs unless they are ignorant of how much money they're losing or they have have highly specific needs that other kinds of bulbs do not provide.

I switched the whole house to CFL. Every light. These bulbs are supposed to last 3-5 years.

I have replaced EVERY CFL BULB IN THE HOUSE within a year. EVERY ONE. GE Brand. No electrical voodoo in the house (I have a line conditioner even at the main). EVERY ONE. I shipped every damn one of them back to GE and Philips for a refund and explaination on why they failed. ZERO response.

Yeah my electric bill went down. $4 a month after replacing EVERY BULB in my house. That is 38 bulbs. You only save oodles of money provided you run them 5 hours a day constantly to cover the cost of the bulb. If have those 5 minute hall and closet lights along with perhaps 2-8 bulbs on for 5 hours (reading lamp, kitchen lights) you lose money. I barely saved money due to the living room lights being on all day. The livingroom, kitchen, and my office are the only high use lights and effectively had to subsidize all the other lights in the home. The $4 a month doesn't cover the $90+ spend on the bulbs...

Now every bulb was replaced back then as the old incandescent ones died off. So they were replaced over a 6 month period when we moved in (The old bulbs were at the oldest 4 years old.) So it can't be blamed on a bad batch of bulbs or a specific store (Target, Home Depot, Menards, and Walmart were sources for the bulbs)

So the CFLs being cheaper is pure bull shit as far as a home is concerned. That useless philips halogen crap in the garage that was supposed to be a 5 year bulb worked out to 8 months and didn't survive the winter.

Total scam in my opinion on CFLs. Until they can get an LED to match a 100 watt bulb (because I like to be able to see in my house rather then some crap ass 60-watt equivalent...) get it as cheap as a normal bulb, I keep my nice 100 watt incadescents thank you. When they burn out I don't have to fork over $3 to replace them.

I won't even get into the discussion about the quality of light from CFLs and LEDs vs. Incandescent bulbs... more useless ineffective crap to protect your new found god...

Telling us it saves $25 bucks a month if bullshit. I'll buy 1. It goes in my garage. If it can survive 3 years I MIGHT consider buying a second one for the bathroom and if that survies another 3 years... then we'll talk. So far this low-energy lighting scam is just that.. a scam as far as my experience has gone.

My criteria from now on: Full Spectrum, 100 Watts, NO STROBING, NO FLICKERING.

CFLs are a joke and LEDs have a long way to go. Too bad it looks like government has to subsidize and legistate to prop up yet another failure... How long till they ban those nice incandescent lights... oh wait...

You had 38 CFL bulbs that all died in less than a year. Meanwhile other people (myself included) are seeing multiple years of life out of ours. As you note, it's can't possibly be something unusual in your case; you have electricl voodoo, and have a line conditioner. That's interesting.

For no particular reason, I'm reminded of the guy I know who complains that every single romantic relationship he's in ends messily. He's wisely concluded that it's impossible for any man to have a healthy, long-term relationship with with women. I'm sure there is some valuable lesson there. [despair.com]